<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>利用return提前终止函数</title>
    <script>
        function getMax(num1,num2){
            if(typeof num1 != 'number' || typeof num2 != 'number'){
                return NaN;
            }
            return num1 > num2 ? num1 : num2;
        }
        console.log(getMax(1,'3'));
    </script>
</head>
<body>

</body>
</html>